This invention relates to a self-adjusting automotive brake pedal actuated switch assembly. Automotive brake pedal actuated switch assemblies are widely used to control a variety of automotive functions when a brake pedal is depressed such as: energizing brake lights, deactivating a cruise control, signaling an anti-lock brake system, signaling a torque converter clutch, and signaling a transmission shift interlock.
In prior art automotive brake pedal mounted and actuated self-adjusting switch assemblies only one switching circuit is available, switch terminals are riveted to the internal switch springs, spring beam force is relied upon to break contacts, and the switch design lacks flexibility.
The limitation of having only one switching circuit in an automotive brake switch will generally require the use of multiple switches because modern vehicles typically require multiple circuits for such functions as: deactivating a cruise control, signaling an anti-lock brake system, signaling a torque converter clutch, and signaling a transmission shift interlock in addition to the usual function of energizing brake lights.
The prior art practice of riveting or welding electrical terminals to internal switch springs doubles the number of electrical connections compared to having electrical terminals that are integral to internal switch springs. Since an objective of switch design is to have as few electrical connections as possible, the additional electrical connections in prior art designs decrease reliability.
The practice of relying upon spring beam pressure to break electrical contacts can present problems when switching higher loads such as brake lamps. Contacts on higher current circuits can weld together due to metal transfer that causes pitting and crowning. The prior art practice of relying on spring beam pressure to break a contact weld may not be successful and cause switch failure.
The basic design of earlier self-adjusting automotive brake switches prevents the switch designer from making minor preplanned modifications to provide a customer with the choice of a variety of features such as additional switching circuits, contacts that open or close when the brake pedal is depressed, mechanical (rather than spring beam pressure) contact breaking, switch sequencing, wiping or non-wiping contact. If prior art switches can provide these type of features, it usually requires either the use of multiple switches or major design and production changes.